Conventionally, radar apparatuses including an aerial unit and an indicator unit are known. JPH04-125483A and JP2003-084059A disclose such radar apparatuses. The aerial unit includes an antenna part (EM radiator) which transmits radio waves while rotating. The aerial unit and the indicator unit are connected to each other by an electric wire. The antenna unit receives the radio waves and outputs them to the indicator unit via the electric wire.
The indicator unit includes a processor and a display unit. The processor performs predetermined signal processing on the received radio waves to create a radar image. The display unit displays the radar image created by the processor.
Note that, in general configurations, a radar antenna and a GPS antenna are separately installed in a ship, whereas in the arts for the radar apparatuses in JPH04-125483A and JP2003-084059A, the GPS antenna is attached to the aerial unit of the radar apparatus. Thus, a compact configuration can be realized.
However, in JPH04-125483A and JP2003-084059A, since the aerial unit and the indicator unit are connected by being wired to each other, in a case of providing a portable display unit, the portable range is limited, which complicates the handling of the display unit. Moreover, in a case of displaying the radar image on a plurality of display units, wiring work becomes complicated.
These kinds of disadvantage are not limited for the ship radar apparatuses, but radar apparatuses installed in other kinds of movable bodies and radar apparatuses disposed on buildings also have similar disadvantage.
Note that, in JPH041992-125483A and JP2003-084059A, the arts of disposing the GPS antenna inside the aerial unit are disclosed, which are simply providing in the aerial unit a GSP antenna which is conventionally disposed above a hull of the ship. Therefore, JPH04-125483A and JP2003-084059A do not disclose nor mention anything regarding disposing in the aerial unit a different type of antenna that is conventionally not disposed above the hull.